Ore-screening apparatus



March 4, 1924.'

1,485,872- G NELSON ORE SCREENING APPARATUS Filed Oct. 14. 1922 Gws/Vfoiz auopmgp Patented Mar. 4, 1924.

UNITED ST GUS; NELSON, 0F DOUGLAS ARIZONA.

ORE-SCREENING APPARATUS.

To all whom it may concern:

Be it known that 1, Gus NnLsoN, citizen of the United States, residing at Douglas, in the county of Cochise and State of Arizona, have invented certain new, and useful Improvements in Ore-Screening Apparatus, of which the following is a specification.

My invention relates to ore screening devices and more particularly to an apparatus provided with a stationary screen, upon which the ore is agitated by means of revolving arms and of a character generally known as grizzly screen.

From actual and extensive tests'made, it has been found that this apparatus will recover about 95% of dry material and about 60% of wet material. Screening devices of known construction cannot extract material above 50%. With other screens it is almost impossible to treat wet ores as they are liable to clog. The present device on the other hand cannot be clogged, as the agitating arms or fingers will drag fine material, deposited on the screen, into the hopper. This is a considerable advantage. These revolving arms or fingers have a double function,

- namely to clean the bars of the screen and also to agitate the ore deposited in the pockets thereof.

In the accompanying drawing, one emboriiment of the invention is illustrated, an V Figure 1 shows a vertical section of the apparatus; I

Fig. 2 is a front view of Figure 1'; the hopper being removed; and

Fi 3 is a transverse section of the bars forming the screen.

On a suitable stand 10 is supported a shaft 11 in bearings 12, which shaft is adapted to be revolved in any suitable manner as, for instance, 'by a belt running over a pulley 13 secured at one end of the shaft. Between the bearings 12, this shaft is preferably provided with two disks 52 in spaced relation to each other. Between these disks are rigidly supported several rods 53, preferably of square cross section and upon which are mounted a plurality of short arms or fingers 54, spaced uniformly along each rod and held by set screws 55. These arms or fingers may be bent, as at 56. It willbe less costly to replace one of these arms 54:, in case of injury, than an arm mounted directly on the shaft 11.

The screen 16 is constructed of a plunarrow tapering downwardly to about its" middle line 31 from where it again is made narrower and having a cross section 32, which is substantially rectangular. This is for the purpose of permitting thecrushed ore collecting between the bars to fall through the screen easier and not tostick' at the bottom thereof. The profile of each bar 17 is substantially of S-shape, see Fig. 1. That is to say, the middle portion 19 is arcuate and swung with a radius from the axis of the shaft 11 and both ends 21 and 22 of the bar run approximately in straight lines from the arc portion, as best seen in Fig. 1. In this manner a depression 20 is formed on the screen to the left of the perpendicular line, as seen in Fig. 1, forming a pocket in the screen, while the lower end of the screen 22 descends at an angle approximately 60 degrees to the horizontal;

The screen is rigidly secured above the 1 shaft 11 in any suitable manner and so positioned that the arms or fingers 54;, when rotating in the direction of arrow Y in Fig. 1, engage in the spaces between the bars,

nearly filling the same, and with the ex 'treme ends protruding above the arcuate middle portion 19 of the screen.

Above the screen is provided a hopper 25 adapted to receive the ore for the screen and at its lower end provided with a spout 26 for carrying olf the oversized lumps of ore. Another hopper 27 is hung beneath the revolving arms intended to collect the smaller lumps of ore that fall through the screen. It is evident that the screens might be graded so that .ore ofdifierent sizes may be collected in diflerent hoppers.

Referring to Figs. 1 and 2, the apparatus operates in the following manner:

The broken up ore is fed into the hopper 25 so that it will be deposited on top of the screen. With the shaft and agitating arms revolving in direction of arrow Y in 1, any lumps of ore collecting in the pocket 20, at the upper end of the arcuate portion of the screen, will be constantly agitated and carried forward and in this manner the smaller lumps of ore will pass through the screen into the hopper 27, while the larger ones will be pushed over the arcuate portion 26 to be collected below the same. 911 account of the fingers 54 fitting snugly in the spaces between the bars 17 of the screens, any part of the ore, that is liable to stick to the bars, will be immediately scraped off by the fingers and fall through the screen into the lower hopper 27. In this manner there is no possibility of clogging the apparatus and it will accordingly run smoothly and perform its work in a very efiicient manner.

The device may be used not only for screening ore but also for screening gravel or sand or any other granular material, the sizes of the revolving fingers and the spacing of the screening bars, may naturally be adjusted to suit conditions.

It is, of course, not necessary to stagger the fingers on the revolving shaft as they ,may also be placed in line, but by placing them in staggered relation the running will be easier and more even as compared with arms placed in alinement, when the apparatus is liable to work more in a jerky manner.

This forms a very simple construction for an ore screening apparatus, as the revolving arms or fingers have only one motion while other devices of the same character resort to cams and reciprocating arms.

The apparatus may be manufactured at a very low cost as suitable material for the screen bars would be old rails reshaped for the purpose. The agitating arms or fingers would be preferablymanufactured from fiat iron bars, but other suitable material may also be selected. In case the fingers 5st become worn'or in any manner injured, they may be replaced by spare fingers, which are more easily detached and attached than would be entire arms.

Having thus described the invention, what is claimed as new is:

1. An ore screening apparatus comprising a screen having spaced parallel bars, parallel sided agitating elements engaging between said bars and arranged to travel in one direction thereof, a revoluble shaft upon which said elements are rigidly mounted, said bars each having an arcuate portion concentric elements are mounted, said revoluble member including a shaft, spaced disks upon said shaft, substantially square sectioned rods rigidly mounted between said disks and arranged parallel to the axis of the shaft, and means for securing said elements upon said rods, said means including hubs onsaid elementsengaging said rods. 7

3. 'An ore screening apparatus comprising a screen having spaced parallel bars, agitating elements each terminating with a bent fingerengaging between said bars and arranged to travel in one direction thereof, hubs on said elements, spaced revoluble disks, square sectioned bars secured between the disks and upon which said elements are mounted by means of said hubs, and set screws on said hubs.

4. An ore screening apparatus comprising a screen having spaced parallel bars, parallel sided agitating elements engaging be tween said bars and arranged to travelin one direction thereof, a revoluble member upon which said elements are mounted, said revoluble member including spaced disks each provided with a stub shaft, rods rigidly 'mounted between said disks and arranged parallel to the axis of said member, means for securing said elementsupon SitlCllOClS,

said elements each terminating with a bent finger, said means including hubs on said elements engaging said rods, and set screws on said hubs.

In testimony whereof I aifix my sig nature.

ens NELSON. a 5. 

